Dont panic, this is gonna be a short one, promised...
Sagem, being a french cellphone manufacturer (among a zillion of other things), has "created" a custom format for their sample based ringtones. Well, to be precise, the file format is the well-known and documented WAVE-file-format (RIFF).
But the codec is not PCM. The wave-files are marked as being "BeCubed Software Inc. : Irat"-encoded (Format 101h).
One doesnt have to be particularly clever to suspect and prove that the used codec certainly is not the claimed one.
Actually, its almost a tradition to use that exact format identifier for self-defined codecs. Its wrong, but common.
Now, lets have a closer look at one of those files. You will notice that the filesize, when compared to the PCM template, has reduced roughly by factor four. Again, you will possibly guess, that is some kind of ADPCM, and you would be right.
When looking really close at those files, you will find out ...
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